diff options
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index a31ee32..94b9bdc 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2350,6 +2350,7 @@ i915_gem_init_ringbuffer(struct drm_device *dev) struct drm_gem_object *obj; struct drm_i915_gem_object *obj_priv; int ret; + u32 head; ret = i915_gem_init_hws(dev); if (ret != 0) @@ -2390,17 +2391,49 @@ i915_gem_init_ringbuffer(struct drm_device *dev) /* Stop the ring if it's running. */ I915_WRITE(PRB0_CTL, 0); - I915_WRITE(PRB0_HEAD, 0); I915_WRITE(PRB0_TAIL, 0); - I915_WRITE(PRB0_START, 0); + I915_WRITE(PRB0_HEAD, 0); /* Initialize the ring. */ I915_WRITE(PRB0_START, obj_priv->gtt_offset); + head = I915_READ(PRB0_HEAD) & HEAD_ADDR; + + /* G45 ring initialization fails to reset head to zero */ + if (head != 0) { + DRM_ERROR("Ring head not reset to zero " + "ctl %08x head %08x tail %08x start %08x\n", + I915_READ(PRB0_CTL), + I915_READ(PRB0_HEAD), + I915_READ(PRB0_TAIL), + I915_READ(PRB0_START)); + I915_WRITE(PRB0_HEAD, 0); + + DRM_ERROR("Ring head forced to zero " + "ctl %08x head %08x tail %08x start %08x\n", + I915_READ(PRB0_CTL), + I915_READ(PRB0_HEAD), + I915_READ(PRB0_TAIL), + I915_READ(PRB0_START)); + } + I915_WRITE(PRB0_CTL, ((obj->size - 4096) & RING_NR_PAGES) | RING_NO_REPORT | RING_VALID); + head = I915_READ(PRB0_HEAD) & HEAD_ADDR; + + /* If the head is still not zero, the ring is dead */ + if (head != 0) { + DRM_ERROR("Ring initialization failed " + "ctl %08x head %08x tail %08x start %08x\n", + I915_READ(PRB0_CTL), + I915_READ(PRB0_HEAD), + I915_READ(PRB0_TAIL), + I915_READ(PRB0_START)); + return -EIO; + } + /* Update our cache of the ring state */ i915_kernel_lost_context(dev); |
